Module Lowest common ancestor (LCA)

Lowest common ancestor (LCA)

**Frequency: 8/10** In many cases where a problem involves querying a path on a tree, there is a high likelihood that the Lowest Common Ancestor (LCA) will be a crucial element in the solution. There are also a lot of problems involving LCA in the next module, Euler tour.

Resources

- [CP Algorithms: Lowest Common Ancestor - Binary Lifting](https://cp-algorithms.com/graph/lca_binary_lifting.html)

Problems

LCA 554 / 559 1300
Distance query 495 / 507 1400
Robot on tree 415 / 440 1400
Heaviest edge 396 / 403 1500
Equal path 304 / 322 1500
Triplet 263 / 268 1500
Path update 307 / 314 1600
Second best minimum spanning tree 157 / 247 1700
Oggy and the cockroaches 54 / 83 1800